I'm sure hoping someone here can help me out with a perplexing problem. Our grey water tank monitor indicates the tank is empty but water from the kitchen and bathroom sinks will not drain into the grey water holding tank but just backs up into the shower pan. We verified the tank is empty and we snaked up the outlet valve just to make sure there was no blockage. We've visually checked and snaked and even rinsed the vent stack and it seems clear. We've plunged both sinks and the shower drain til our arms almost fell off. We tried a drain cleaner and snaked all drains. We got a flush master attachment thingy so we could back flush the tank from the outlet valve. So far nothing has worked. Water still just goes directly from the sinks to the shower pan and no water enters the grey tank. I'm getting really tired of baling the shower pan so if you have any ideas or suggestions I'd love to hear them. Thanks;Sue

do you have more than one grey tank. does the shower drain into the black tank?bumpy

Is this a new RV? Take it back to the dealer if it is. If not, was it ok and suddenly something changed?Maybe the drain from the sinks and shower join before going into the grey tank and something is blocking the combined pipe before entering the tank.Maybe a plumber would have some kind of snake that could clear the blockage???Maybe you could back fill the tank and push the blockage up to where you could get it out.The alternative is to take things apart and find the blockage.

It sounds like the vent pipe on the tank might be blocked. Like electricity, water takes the path of least resistance. If the vent pipe is blocked, you tank becomes a big, high pressure bubble. When water from your sink intersects the shower drain, the shower pan is easier to get to than the tank. You could test this by running your sinks with your drain open since that would prevent pressure buildup.

:h what bumpy said and get back with us.

Thanks Everyone for your lightening fast responses to my question. Bumpy, I'm pretty sure there is only one grey tank because there is just a very small kitchen sink and bathroom sink and shower to drain into it and they are all in a line on the same wall of the trailer. There is only one grey tank on the fill monitor. I'm pretty sure the shower drains into the grey tank. We've done stuff like add soap to the water in the sinks to make sure that what we are seeing in the shower pan is the actually coming from the sinks. Tenbear, the trailer is new to us. We just bought it privately - 'just' is the operative word here. Your thoughts about a possible drain blockage after the sinks and shower join and before it enters the tank are similar to mine. I can't figure out how to get at it to check though. A snake doesn't seem to be helping but maybe I'll give it another shot - maybe with a new and better snake. Your suggestion about back filling the tank is probably worth a try. We got it about half filled when we were back flushing - mostly because we were trying to test whether the monitor was even working -0 which it was. Then we emptied it. I'll try again tonight and fill'er right to the top to see what happens. Camp Forrest..I get what you mean about the vent and that was our first suspicion also but running the sinks with the drain open or closed makes no difference. Too bad , eh? I'll post later with the 'results' of tonight's trailer fixing event. Thanks again to all of you!Sue

Grey water in Shower Pan | Good Sam Community

Mesakeca
Explorer
Sep 16, 2013
Holding Tank Dilemma Update:
Ok, so this is pretty embarrassing but I thought I'd provide feedback in case anyone else is suffering the same problem. It turns out that the tank that we were sure was empty was actually the BLACK WATER tank. Not the grey water - which was in fact full despite what the obviously malfunctioning monitor said. What is especially troubling to me is that my hubby just ASSUMED the valve he was opening (into a bucket, no less) was the grey water valve. I mean, REALLY!!, why would anyone make that assumption! Of course, I'm guilty too because I just 'assumed' the valve covers were marked. Very lucky for him and the rest of us that the BW tank was actually empty. (we live on a farm where there is a lot of animal fecal matter around anyway - but still, EEEWWWW!!).
So, the lesson to me and possibly to others is 1.) don't trust your tank monitors; 2.) Don't just assume which valve is black and which is grey. 3.) Don't always assume your spouse actually knows what they're doing. :-)
Anyway, it's all good now. Thanks to you all for your helpful advice.
Sue
Grillmeister
Explorer
Sep 16, 2013
Glad you figured it out and thanks for posting the outcome.
tenbear
Explorer
Sep 16, 2013
Glad to hear the problem is solved.

You can tell the difference between the valves by their size. The pipe from the black tank is 3" dia. The grey is much smaller.
tenbear
Explorer
Sep 16, 2013
I guess its a lesson for us too. Never assume the OP knows what they are doing. :h :B
Bumpyroad
Explorer
Sep 16, 2013
tenbear wrote:
I guess its a lesson for us too. Never assume the OP knows what they are doing. :h :B

now that was a little harsh to a new member. :)
bumpy
teddyu
Explorer
Sep 16, 2013
Bumpyroad wrote:
tenbear wrote:
I guess its a lesson for us too. Never assume the OP knows what they are doing. :h :B

now that was a little harsh to a new member. :)
bumpy

Not sure if this is harsh or not - or maybe a statement of fact. Part of solving any issue is assuming the OP is providing accurate information. Blind troubleshooting is difficult at best provided the information is accurate. Inaccurate information leaves us all guessing.

It is nearly impossible to determine the experience level of a new poster. With this problem, directing the OP to ensure that they are dumping the Grey not the Black tank would have been condonsending.

The forum is lucky the OP provided the feedback (solution to the problem) no matter how simple the solution was or the mistake that caused this thread. Hopefully the OP will return and post again.
tenbear
Explorer
Sep 16, 2013
Bumpyroad wrote:
tenbear wrote:
I guess its a lesson for us too. Never assume the OP knows what they are doing. :h :B

now that was a little harsh to a new member. :)
bumpy

Sorry, I was only joking. I'll go and stand in the corner.
Bumpyroad
Explorer
Sep 16, 2013
note the :)
bumpy
DiskDoctr
Explorer
Sep 16, 2013
Sink water coming up the shower drain...yep, I trusted our grey water sensors 'once' too...ONCE :B

Glad the fix was simple! Sounds like you have a sense of humor about it- which can serve you well in the coming camping trips.

Enjoy the up's and down's and never be afraid to laugh at yourself ;)
Dakzuki
Explorer
Sep 17, 2013
tenbear wrote:
Glad to hear the problem is solved.

You can tell the difference between the valves by their size. The pipe from the black tank is 3" dia. The grey is much smaller.

Not always, but if there's a smaller one that should be the gray.

Forum Discussion

Grey water in Shower Pan

About Technical Issues

Related Content

connecting grey tanks to get more capacity for the shower

Maiden voyage success - question about grey water tanks

Stupidity leads to overflowing Grey Water inside trailer

Grey water pipe and fitting

Outside Shower